We introduce a new cryptographic technique that we call universal re-encryption. A conventional cryptosystem that permits reencryption, such as ElGamal, does so only for a player with knowledge of the public key corresponding to a given ciphertext. In contrast, universal re-encryption can be done without knowledge of public keys. We propose an asymmetric cryptosystem with universal re-encryptio...

key distribution is an important problem in wireless sensor networks where sensor nodesare randomly scattered in adversarial environments.due to the random deployment of sensors, a list of keys must be pre-distributed to each sensor node before deployment. to establish a secure communication, two nodes must share common key from their key-rings. otherwise, they can find a key- path in which ens...

Signcryption tag-KEM (Key Encapsulation Mechanism with a tag) is an authenticated tag-KEM for generic construction of hybrid signcryption. Signcryption tagKEM allows the sender to encapsulate a symmetric key along with a tag so that the receiver can authenticate the sender, the key, and the tag. We present a definition for the security of signcryption tag-KEM which is suitable for a recent sign...

Owing to the security requirements of wireless sensor network, the background of Wireless Sensor Network (WSN) is to be analyzed with different threats and attack models. Physical compromising of sensor nodes by an adversary is an emerging problem in sensor network and accordingly, it is necessary to provide an environment with efficient key management techniques due to resource constraints on ...

Wireless sensor networks are being deployed for a wide variety of applications. It is an important challenge to find out practical security protocols for wireless sensor networks due to limitation of power, computation and storage resources. Symmetric key techniques are attractive due to their energy efficiency. But the drawbacks of symmetric key techniques are evident in terms of key managemen...

Sensor networks are characterized by strict resource limitations and large scalability. Many sensor network applications require secure communication, a crucial component, especially in harsh environments. Symmetric key cryptography is very attractive in sensor networks due to its efficiency, but establishing a shared key for communicating parties is very challenging. The low computational capa...

Throughout the history of cryptography, hundreds of cryptosystems have been developed. The earliest ones, as well as many later ones, relied on the complete secrecy in transferring keys between the sender and recipient. These kinds of systems, called secret key cryptosystem, have just a single key which is used for both encryption and decryption; therefore, these systems are more frequently kno...

Pervasive computing environments find their practical manifestations through wireless sensor networks, which sense a relationship amongst themselves and the environment. Currently the proposed keying schemes for ensuring security, in wireless sensor networks, may be classified into public and private keying schemes, or their hybrid. However, an investigation in peer work underpins the fact that...

Key management for anonymous communication in mobile ad hoc networks is a critical but unsolved problem. Many current anonymous mobile ad hoc routing protocols assume that mobile users share pairwise secrets before they start an anonymous communication session. This assumption is impractical for many ad hoc scenarios where pairwise shared keys are difficult to be set up in advance. Public-key b...